This adds support for "generator effect strips", which don't need necessarily an input strip and my version of Matt Ebb's [ #5035 ] 'Solid Color' sequence strip. TODO: With a little bit more tweaking it will be possible to make animated effect plugins and my still unfinished "Bake"-Strip. For the 'Solid Color'-Effect, to quote Matt: This is nice and simple, just provides a solid colour that's set in a colour picker in the properties popup. This is something we've needed for a long time, and I got totally sick of having to make 'black.png' and 'white.png' just to do fades, so I coded this.